package com.comleader.ldmapdownload.util;

import com.graphhopper.util.shapes.GHPoint;

/**
 * 坐标转换工具类
 */
public class TransLocationUtil {
    private static double pi = 3.14159265358979324D;// 圆周率
    private static double a = 6378245.0D;// WGS 长轴半径
    private static double ee = 0.00669342162296594323D;// WGS 偏心率的平方

    /**
     * 中国坐标内
     *
     * @param lat
     * @param lon
     * @return
     */
    public static boolean outofChina(double lat, double lon) {
        if (lon < 72.004 || lon > 137.8347)
            return true;
        if (lat < 0.8293 || lat > 55.8271)
            return true;
        return false;
    }

    public static double transformLat(double x, double y) {
        double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y
                + 0.2 * Math.sqrt(Math.abs(x));
        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;
        ret += (160.0 * Math.sin(y / 12.0 * pi) + 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;
        return ret;
    }

    // 84->gcj02
    public static double transformLon(double x, double y) {
        double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1
                * Math.sqrt(Math.abs(x));
        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;
        ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0
                * pi)) * 2.0 / 3.0;
        return ret;
    }

    /****
     * 地球坐标转火星坐标
     * @param lon
     * @param lat
     * @return
     */
    public static GHPoint transform(double lon, double lat) {
        GHPoint ghPoint = new GHPoint();
        if (outofChina(lat, lon)) {
            ghPoint.lon = Double.valueOf(lon);
            ghPoint.lat = Double.valueOf(lat);
            return ghPoint;
        }
        double dLat = transformLat(lon - 105.0, lat - 35.0);
        double dLon = transformLon(lon - 105.0, lat - 35.0);
        double radLat = lat / 180.0 * pi;
        double magic = Math.sin(radLat);
        magic = 1 - ee * magic * magic;
        double sqrtMagic = Math.sqrt(magic);
        dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
        dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
        double mgLat = lat + dLat;
        double mgLon = lon + dLon;
        ghPoint.lon = mgLon;
        ghPoint.lat = mgLat;
        return ghPoint;
    }

    // gcj02-84
    /**** TODO
     * 火星坐标转地球坐标
     * @return
     */
    public static GHPoint gcj2wgs(GHPoint targetPoint) {
        double lon = targetPoint.getLon();
        double lat = targetPoint.getLat();
        double lontitude = lon
                - (((Double) transform(lon, lat).getLon()).doubleValue() - lon);
        double latitude = (lat - (((Double) ( transform(lon, lat))
                .getLat()).doubleValue() - lat));

        return new GHPoint(latitude,lontitude);
    }

}
